A member of Ukraine’s elite Berkut riot police force assaulted and humiliated a naked protester after he was detained in freezing cold temperatures in Kiev, according to a video posted Thursday.

The Ukrainian interior ministry swiftly apologised for the horrific incident, which recalled notorious prisoner abuse scandals like that at Abu Ghraib prison in Iraq.

The man had apparently been arrested during the clashes between police and protesters that have rocked Kiev over the last days.

The video, which was posted on YouTube and was rapidly broadcast by Ukrainian opposition channels, shows the arrested protester completely naked except for his socks and being roughly pushed into a police bus.

But he is then called back and is forced to stand still on the snow in the freezing temperatures while a police officer in a balaclava films him with his mobile phone.

He is then forced to pose for pictures clutching a spade, alongside another balaclava-clad officer who mockingly puts his arm around the prisoner. This officer then hits him roughly on the back of the head.

The officer then leads the prisoner back to the van, giving him a final kick. Another officer, whose face is not concealed, then appears to reproach the officer in the balaclava for his excess.

The interior ministry said it was apologising for the “unacceptable actions of the people in police uniform”.

It said an internal probe had been launched into the circumstances of the incident.

Interior Minister Vitaliy Zakharchenko was quoted as reminding his staff of the “inadmissability of of such actions and” and called on police to “stick to the norms of the law and morals”.

The head of the protest camp on Kiev’s Independence Square, known locally has the Maidan, said that the victim had now been identified and was being given treatment.

“His name is Mykhailo Gavrylyak. Now he is the Maidan self-defence headquarters and is being given treatment,” Andriy Parubiy wrote on Facebook.